Sound

When i go to Advanced setup -> User interface -> Use sound signal I have the option checked but when i get a virus it does'nt make any sound. Not even a beep. I readed ESET Help and it says: Use sound signal - If a virus is found, the program will sound a warning but it does nothing. I really want a sound, when a virus is detected. What should i do? And i am ABSOLUTELY shure that there's nothing wrong with my speaker and soundcard.